The proposed research represents a novel application of low temperature (10K) solid-state 67Zn and 25Mg NMR applied to proteins and their model systems. The principal aim for the proposed research is to continue our efforts in establishing a relationship between 67Zn and 25Mg magnetic resonance parameters (quadrupole coupling constants, shielding tensors and their relative orientations) and the structure/function relationships for known Zn- and Mg-metalloproteins and extrapolating those relationships to proteins where the role of the metal is less defined. These experiments are performed in concert with ab initio electronic structure calculations. The combination of these two methods provides a firm basis for the "chemical" understanding of the role these metals play in their respective proteins. Additionally, triple resonance experiments (1H, [15N or 31P], [25Mg through 67Zn]) are proposed to facilitate the identity of neighboring ligands and the determination of selective bond distances between the metal of interest and the directly bonded atom of the ligand. The results of these experiments are critical for the mechanistic understanding of the role the metal plays in the protein of interest, e.g. Mg 2+ in E. coli alkaline phosphatase. [unreadable] [unreadable]